Hot water generator



March 1, 1966 ca. STABENOW 3,237,611

HOT WATER GENERATOR Filed May 13, 1964 2 Sheets-Sheet 1 INVENTOR.

G. STABENOW HOT WATER GENERATOR March 1, 1966 2 Sheets-Sheet 2 Filed May 13, 1964 IN VE N TOR. fiemy Jiadman;

United States Patent 3,237,611 HOT WATER GENERATOR Georg Stabenow, 125 Analomink St., East Stroudsburg, Pa. Filed May 13, 1964, Ser. No. 367,055 3 Claims. (Cl. 122-356) This invention relates to hot water generators and in particular to hot water generators of the type in which water is circulated through tubes provided for that purpose which are subjected. to heated gases.

It is a principal object of this invention to provide a hot water generator of the above type which reduces to a minimum the number of external headers required thus providing a lighter, more compact, more economical structure and which reduces the pressure drop of the circulating fluid thereby maintaining the fluid pressure.

It is a further object of this invention to provide a hot water generator in which a reduction in the corrosion of the Water carrying tubes is achieved as well as permitting a reduction in the amount of refractory used in the construction of the generator.

It is also an object of this invention to provide a hot water generator in which a reduction in fluid pump capacity is achieved concurrently with the realization of all of the foregoing objects.

Other objects and advantages will be apparent from the following description and drawing.

FIGURE 1 is a side view partially broken away and in section of the hot water generator of this invention.

FIGURE 2 is a perspective view of the internal tube construction of the hot water generator of this invention showing the external headers and provided with arrows schematically showing the direction of flow of the water through the tubes.

FIGURE 3 is a sectional view taken along the lines and arrows III-III indicated in FIGURE 2 of the ar- Fuel is burned in burner wall 16, roof 17, base 18 and side walls 19 and 20. Ac-

cess doors 45 and 46 are located on side wall 19.

Within the housing 10 are arranged a series of fluid carrying tubes arranged in banks as at 30 which comprise a series of tubes arranged in parallel and said bank located tangent to insulation 40 of side walls 19 and 20 as return fluid carrying tube bank 41 is to insulation 40 at base 18. Insulated baflle wall 25 is located between the front wall 15 and the back wall 16 and attached to the sides 20 and 19 of housing 10, leaving a space at the bottom between the baffle 25 and the insulation 40 at the base 18 of housing 10. This arrangement permits the passage of combustion gases from burner 12 through outlet 13 to flue 14.

The fluid carrying tubes situated inside housing 10 are provided with external inlet headers 30 provided with orifices 31, external distribution header 32 and provided integrally therewith discharge header 33. Discharge header 33 is separated from distribution header 32 by means of plug 34 shown in FIG. 2. The fluid carrying tubes located between baifle 25 and rear wall 16 within housing 10 are generally characterized as economizer circuit 35. The fluid carrying tubes located below baflle 25 on the side walls 19 and 20 are part of the main fluid heating circuit.

The operation of the hot water generator according to this invention can best be understood by referring to the 3,237,611 Patented Mar. 1, 1966 "ice perspective drawing in FIG. 2. Fuel is burned in the burner 12 of FIG. 1 and the combustion products come into heat exchanging contact with the fluid carrying pipes at burner opening 13. The products of combustion then travel generally along the path designated by the arrows X, Y and Z, passing underneath the insulated baflle 25 and then rising through the economizer circuit 35 as shown at arrow Z to eventually pass out of the schematically shown flue at 14. Cold water is introduced into header 30 at arrow A and from there passes through a bank of parallel fluid carrying tubes 36, generally rearwardly tangent to the roof of the combustion chamber and to each other over the baflle 25 and into the economizer circuit 35. The tubes at the bottom of economizer circuit 35 then return the water to the front of the hot water generator by means of tubes 41 located tangent to insulation 40 in FIG. 1 to the distribution header 32. The vertical arm of the L-shaped distribution header 32 is provided with orifices (not shown) for the fluid carrying tubes which reenter the combustion chamber in a bank of tubes 37 to tangentially follow the insulation 40 of side wall 20 of housing 10 (FIG. 1), to the insulated baflle 25. At this point they are bent in a U-shape to provide a free path for the flue gases X in their travel under insulated baffle 25. The bank of tubes 37 then extend transversely across the housing 10, and return to baflle 25 to undergo a similar bend at baflle 25 to return the bank 37 to a tangential position along the insulation 40 of side wall 19 (FIG. 1). The portion of the bank of tubes 37, located between the baflle 25 and the insulated floor 40 of the housing 10 are provided to extend to the rear 16 of housing 10 in order to give the generator the maximum heat exchanging tube surface area. The bank of tubes 37 then travels toward the front 15 of housing 10, upwardly toward the roof 17 of housing 10 and then rearwardly along side wall 19, bend tangential to vertical baffle 25, transversely cross the front of baffle 25 and then travel forward tangent to side wall 20, ending at external discharge header 33.

The arrangement of tubes in the hot water generator of this invention thus provides for fluid flow which is partly counterflow to the passage of heating gases and partially concurrent with passage of the heating gases throughout the generator. The tubes in the tube banks arranged substantially tangent to each other reduces the amount of insulation necessary in the walls of the generator for eflicient generator operation.

The generator thus provided has been found to be efficient in fuel consumption and maintenance of fluid pres sure from inlet to outlet. It can be built compactly and simply. In addition, by decreasing the number of headers in the system and decreasing the temperature of the fluid returning from the economizer circuit to the combustion chamber it has been found that the capacity of the fluid pump used for circulating the fluid within the generator can be greatly reduced without decreasing the efliciency of the system. By utilizing the free heating of the initial fluid by the arrangement of the inlet header 30 and tubes 36 there is a decrease in the corrosion of the fluid carrying tubes in the economizer circuit 35 as these tubes are maintained at a temperature above the dew point of the products of combustion. In this manner too, the return temperature of the water to the [forward distribution header 32 is lower than in previous designs of hot water generators.

Having disclosed the invention according to an example of its preferred embodiment it will be apparent to one skilled in the art that the invention is not limited to that embodiment but is broad enough to include all equivalent embodiments.

It is claimed:

1. A hot water generator comprising a housing, heating means, and fluid carrying means; said housing comprising an external shell lined internally with insulation, said shell comprising a roof, a floor, front and the back walls and side walls, and insulated 'baffle means, said baflle means provided to separate the area proximate to the heating means from the area remote from said heating means and extending vertically downward from the roof of said housing and attached to the side walls thereof and ending at a point near the floor of said housing, said heating means comprising a gas heater disposed on the front wall and communicating with the interior of said housing proximate to said heating means, and flue means for emitting the spent products of said heating means disposed in the roof of said housing at a place remote from said heating means, said fluid carrying means comprising first, second and third fluid carrying means and tube means, said first fluid carrying means transversely disposed external to said housing proximate to said heating means and arranged to communicate with said housing in a direction toward said flue means, said first fluid carrying means then returning from the end of said housing proximate to said flue means into the area proximate to said heating means along the floor of said housing, to the front wall thereof, first tube means interposed between said first fluid carrying means and said second fluid carrying means, said tube means comprising a bank of tubes, said bank being located initially proximate to the heating means tangent to the roof of said housing and running to a portion of the housing remote from said heating means, said bank being configured to expose a large surface area of fluid carrying tube means and positioned within said housing remote from said heating means said bank returning along the floor of said housing to the front wall thereof communicating with said second fluid carrying means, said second fluid carrying means arranged to distribute fluid to second tube means communicating therewith and with the interior of said housing said tube means comprising a bank of tubes arranged tangent to each other and in parallel tangent to the Walls of said housing except where said bank of tubes traverse the housing, said tube means communicating with said third fluid carrying means, said third fluid carrying means provided to discharge the heated fluid from the generator.

2. A hot water generator comprising a housing, heating means and fluid carrying means, said housing comprising an insulation lined shell having a roof, a floor, front and back walls, said shell divided into two communicating compartments by an insulated wall means located between said front and back walls, dependent from said roof ending at a point above the floor of said housing, heating means comprising burner means located on the front wall of said housing communicating with the interior of the first compartment of said housing, flue means located on the roof of said housing communicating with the interior of the second compartment of said housing and comprising means for the removal of spent heating gases, said fluid carrying means comprising first, second and third tube means, said first tube means comprising a header provided for communication with a plurality of tube means, said header located external to the front wall and roof of said housing, said header provided with orifices to said tube means, said tube means communicating with said header and extending in a parallel oriented bank into said housing at a point near the roof of said housing, said tube means located tangent to each other and to the insulation of said roof and extending from the front wall of said housing to the rear wall of same, said tube means in bank provided with plurality of turns at the back wall of said housing and at said insulated wall means on the side proximate to said flue means, said turns continuing from the roof of said housing to the floor where said bank of tube means extends to the front wall of said housing tangent to the floor of said housing; said second tube means comprising a'header located external to the front wall of said housing, said header communicating with the plurality of aforesaid tube means, and provided with distributing means for providing fluid to a second bank of tube means, said second tube means communicating with the interior of said housing tangent to adjacent tube means and tangent to the walls thereof and traversing said housing tangent to said insulated wall means near the roof of said housing and substantially parallel to said insulated Wall means near the floor of said housing said bank of tube means communicating with said third tube means, said third tube means comprising a header and discharge means.

3. A hot water generator comprising a housing divided into a burner section and an economizer section, burner means at one end of the burner section, flue means in the economizer section and baffle means suspended from the roof of said housing separating the two sections to permit the flow of combustion gases thereunder, an inlet manifold disposed above the burner end of said housing, an external manifold disposed adjacent the lower end of the burner end of the housing, first tube means connected to said inlet manifold and extending into said housing, along the roof thereof into the economizer section, downwardly through the economizer section and then returning to the burner end of the housing along the floor thereof and into said external manifold, an outlet manifold disposed externally of the burner end of the housing, second tube means connected to said external manifold extending around the inner side-wall surfaces of the burner section of said housing and spaced away from said baflle means to permit the flow of combustion gases thereunder and returning to said outlet manifold disposed externally of the burner end of the housing, said manifolds and tube means being arranged and constructed to permit the continuous flow of water therethrough from the inlet manifold to the outlet manifold.

References Cited by the Examiner UNITED STATES PATENTS 2,860,612 11/1958 Surham 122406 X 2,994,308 8/1961 Stabenow 122406 3,081,749 3/1963 Stabenow 122406 KENNETH W; SPRAGUE, Primary Examiner. 

3. A HOT WATER GENERATOR COMPRISING A HOUSING DIVIDED INTO A BURNER SECTION AND AN ECONOMIZER SECTION, BURNER MEANS AT ONE END OF THE BURNER SECTION, FLUE MEANS IN THE ECONOMIZER SECTION AND BAFFLE MEANS SUSPENDED FROM THE ROOF OF SAID HOUSING SEPARATING THE TWO SECTIONS TO PERMIT THE FLOW OF COMBUSTION GASES THEREUNDER, AN INLET MANIFOLD DISPOSED ABOVE THE BURNER END OF SAID HOUSING, AN EXTERNAL MANIFOLD DISPOSED ADJACENT THE LOWER END OF THE BURNER END OF THE HOUSING, FIRST TUBE MEANS CONNECTED TO SAID INLET MANIFOLD AND EXTENDING INTO SAID HOUSING, ALONG THE ROOF THEREOF INTO THE ECONOMIZER SECTION, DOWNWARDLY THROUGH THE ECONOMIZER SECTION AND THEN RETURNING TO THE BURNER END OF THE HOUSING ALONG THE FLOOR THEREOF AND INTO SAID EXTERNAL MANIFOLD, AN OUTLET MANIFOLD DISPOSED EXTERNALLY OF THE BURNER END OF THE HOUSING, SECOND TUBE MEANS CONNECTED TO SAID EXTERNAL MANIFOLD EXTENDING AROUND THE INNER SIDE-WALL SURFACES OF THE BURNER SECTION OF SAID HOUSING AND SPACED AWAY FROM SAID BAFFLE MEANS TO PERMIT THE FLOW OF COMBUSTION GASES THEREUNDER AND RETURNING TO SAID OUTLET MANIFOLD DISPOSED EXTERNALLY OF THE BURNER END OF THE HOUSING, SAID MANIFOLDS AND TUBE MEANS BEING ARRANGED AND CONSTRUCTED TO PERMIT THE CONTINUOUS FLOW OF WATER THERETHROUGH FROM THE INLET MANIFOLD TO THE OUTLET MANIFOLD. 